Everyone ages differently. Two 50-year-olds who have lived the same number of years may have different biological ages due to a range of inherent and extrinsic factors, resulting in different rates of ageing and variable degrees of risk for disease and early mortality.
Disease, poor nutrition, smoking, and other lifestyle factors all contribute to biological ageing that extends beyond chronological age. In other words, you’re becoming older faster than you should. For the first time, researchers established a relationship between increased biological age and muscular weakening as measured by grip strength, which serves as a proxy for total strength capability. According to findings published in The Journal of Cachexia, Sarcopenia, and Muscle, grip strength falls with biological age.
Researchers at Michigan Medicine examined the relationship between biological age and grip strength in 1,274 middle-aged and older people using three “age acceleration clocks” based on DNA methylation, a process that provides a molecular diagnostic and estimation of the rate of ageing. The watches were created in response to several studies on early mortality, Alzheimer’s disease, inflammation, diabetes, cardiovascular disease, cancer, physical disability, and so on.
The findings demonstrate that older men and women had poorer grip strength and biological age acceleration throughout the DNA methylation clocks.
“We’ve known that muscular strength is a predictor of longevity, and weakness is a powerful indicator of disease and mortality,” said Mark Peterson, PhD, M.S., lead author of the study and associate professor of physical medicine and rehabilitation at the University of Michigan. “This implies that if you keep your muscular strength up throughout your life, you may be able to avoid many prevalent age-related ailments. We know that smoking, for example, is a strong predictor of disease and mortality, but we now know that muscular weakness may be the new smoking.”
According to Jessica Faul, PhD, M.P.H., a research associate professor at the University of Michigan Institute for Social Research and a co-author of the study, the study’s true strength was the eight to ten years of observation. Lower grip strength was associated with accelerated biological ageing up to a decade later. According to past research, low grip strength is an extremely significant predictor of unfavourable health outcomes. According to one study, it even exceeds systolic blood pressure, the clinical gold standard for diagnosing heart problems, as a predictor of cardiovascular events such as myocardial infarction. Peterson and his colleagues have previously shown a clear link between chronic illness and mortality across populations, as well as poor health.
According to Peterson, this data, together with their previous findings, suggests that doctors should utilise grip strength to screen patients for future risk of functional decline, chronic illness, and even early mortality.
“Screening for grip strength would allow us to develop treatments to postpone or prevent the beginning or advancement of these adverse’age-related’ health outcomes,” he explained. “We’ve been urging physicians to start using grip strength in their clinics, but only in geriatrics has this been done. However, despite hundreds of articles demonstrating that grip strength is a very good metric of health, few individuals use it.”
Researchers believe that further study is needed to completely understand the association between grip strength and age acceleration, as well as how inflammatory conditions impact mortality and age-related weakening. Previous study has linked chronic inflammation with age, or “inflammaging,” to an increased risk of death in the elderly. This inflammation is also connected to decreased grip strength and may be a crucial predictor of the association between decreased grip power and chronic illness multimorbidity as well as disability. According to Peterson, studies should also look into how behavioural and lifestyle factors, such as nutrition and exercise, affect grip strength and the rate at which individuals age.
“Healthy eating choices are crucial, but I believe that regular exercise is the most important thing that someone can do to maintain health over the lifespan,” he stated. “We can demonstrate it using a biomarker like DNA methylation age, as well as a clinical trait like grip strength.”